Instructions for using user certificates

In email clients (Outlook, Thunderbird, Apple Mail, BTU webmail interface, etc.), a personal SSL certificate can be used to sign and/or encrypt emails.

In Internet browsers (Internet Explorer, Mozilla Firefox, Safari, etc.), BTU members can use their personal SSL certificate to log in to various BTU web services as well as the BTU intranet.

Windows/Outlook

Mozilla Thunderbird

Mac OS X/Apple Mail

macOS/Outlook

Webmail-System der BTU

 Mozilla Firefox

Change certificate password

Export certificate

General information about email encryption

An email can only be sent in encrypted form if the sender of the email (or their email program) has the public key portions of the SSL certificates of all recipients (To, Cc, Bcc).

An encrypted email can only be decrypted (read in plain text) by a recipient if they have the secret key (private key) of their own SSL certificate.

It is not advisable to forward an encrypted email as an attachment. In the best case, you can and should quote from encrypted emails.

Explanation: If an encrypted email is forwarded as an attachment, the new recipient will not be able to read it because they do not have the secret key part of the original recipient and are not authorised to have it.